Methods are known from vehicle technology for controlling and/or regulating an automatic transmission of a vehicle depending on the slope of the route slope driven. In an automatic transmission with automatic gear ratio selection it is customary to select the desired speeds, for example, from specific input variables, such as, for example, from the accelerator position and the driver command connected to it. The speeds are varied therein depending on the current uphill grades or current driving resistances of the vehicle, the needed power requirement in the vehicle is determined in this way.
It has been shown, that the current uphill grade reflects only an instantaneous value and not a driving environment, such as, for example, if the vehicle is driving on a winding mountain pass road. A gear ratio selection corresponding to level ground is thus carried out in the known processes, while the vehicle travels over a short flat distance as it drives on a winding mountain pass road, since this corresponds to the current grade. The engine speed expected for driving over mountains is thus not engaged.
A method is known and a device for controlling the shift point of an automatic transmission depending on the slope of the route driven are known from patent publication DE 44 40 706 A1. So-called oscillating shifts are effectively prevented with this method. For this purpose, the current slope value which is utilized for controlling the vehicle transmission is strongly filtered in the process. A time offset between the utilized slope value and the current slope is achieved by means of filtering of the respectively current slope values. The aforementioned problems can occur again, through this measure, if the time offset is exceeded.
An electronic operating control system for a motor vehicle powertrain is known, from patent publication DE 38 31 449 C2. This electronic operating control system also utilizes operating state variables, in order to take into consideration the topographic conditions of the driving route during control. The known operating control system is also unable to prevent the described problem.